1. Field of the Invention
The present invention relates to an improvement made to devices for taking up loose products from the ground, with a view to ensuring their transfer from the take-up site to a discharge zone. It relates equally to vehicles fitted with such a device, and more particularly to a new type of lawn mower.
2. Discussion of the Prior Art
In many spheres, the problem is encountered of having to take up a material from a site with a view to transporting it into another zone. Such a problem arises in particular during the maintenance of green spaces (sports fields, golf courses, lawns, parks . . . ) in order to pick up grass after mowing, remove leaves or other waste.
In the continuation of the description, the invention will be described for such an application (picking up grass after or during mowing), but it is plain that this is not limitative and that the invention could be applied in other spheres where similar problems arise, such as for example on machines used for cleaning the ground, particularly roads and pavements.
At the present time, the equipment serving to carry out mowing operations is constituted by a "tractor" type vehicle on which is mounted an assembly which serves not only for cutting the grass, but also for picking it up and storing it with a view to its disposal. Such an assembly, one embodiment of which in current use at the present time is shown in the accompanying FIG. 1, is constituted essentially by a head, designated by the general reference (1), movable close to the surface of the ground, mounted in general under the chassis of the vehicle (2) (or in front of the latter), these heads comprising means serving to cut and to take up the grass which is transferred by means of a connecting pipe (3) to a storage enclosure (4) carried by the vehicle, which enclosure can appear in different forms and can consist for example of a simple bag, a fixed or tipping hopper or, as is shown in the accompanying FIG. 1, of an assembly constituted essentially by two shells (5, 6) which define between them the volume for storage of the material. In such an embodiment, the two shells (5, 6) are mounted at the rear of the vehicle through the intermediary of a beam (7), one shell (5) being mounted fixed to the said beam (7) and the other shell (6) being capable of pivoting on a horizontal axis (8). Means constituted for example by a jack (9) and a system of "gas caliper" type (10), serve to control the movements of the shell (6) with respect to the fixed shell (5), so that they can be maintained in separated position as is shown in said FIG. 1 when it is desired to proceed to an operation of unloading the hopper after filling and so that they are maintained pressed against one another in order to define the storage volume during the mowing operation per se.
In such assemblies, in order to carry out the transfer of the grass cut by the cutting members per se (11), a turbine (12) is used which serves to transfer the grass through the connecting pipe (3) which opens into the upper part of the storage enclosure (4) and, in the present case, to the interior of the fixed shell (5). The most widespread solution, shown in the accompanying FIG. 1, consists of disposing the turbine (12) either vertically as shown in FIG. 1, or horizontally; the grass may or may not be subject to the action of the blades of said turbine.
One of the main problems which arise with such assemblies in which the turbine is associated directly with the cutting head, resides in their lack of effectiveness, particularly when the grass is wet, taking into account the long distance between said turbine and the zone of discharge to the interior of the storage enclosure. Moreover and especially, such a design (cutting member and integrated turbine) leads to a large overall width dimension, since the turbine projects laterally with respect to the cutting head per se, and also to the complex construction of power transmission assemblies, especially when the turbine is disposed vertically, necessitating in general the use of pinions, bevel gears, universal joints. . . . Lastly, such integrated assemblies (cutting head and turbine) are difficult to assemble and disassemble, which complicates their maintenance.